Partial Discharge Monitoring

Early Detection for Transformer Insulation Health

We supply Qualitrol’s industry‑proven Partial Discharge (PD) monitoring systems, designed to give power asset owners clear, real‑time visibility into transformer insulation health. PD activity is one of the earliest indicators of developing insulation faults, and early detection is essential to preventing costly failures. By providing proven UHF‑based monitoring equipment backed by Qualitrol’s global technology leadership, we help our customers strengthen operational reliability and support condition‑based maintenance strategies.

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Qualitrol QPDM Transformer Partial Discharge Monitoring System, front-1

Application Overview

Qualitrol PD monitoring systems are engineered for continuous, online use in power transformers, GIS, and other high‑voltage assets. These systems can be integrated during transformer manufacture with internal UHF sensors or installed later using external window or drain‑valve sensors. As a distributor, we provide complete solutions—hardware, software and installation support—that enable utilities to detect PD activity, classify defect types and correlate behaviour with load or switching events. This helps organisations monitor insulation health without taking equipment offline.

What We Solve For

Insulation defects inside a transformer often develop gradually and may remain undetected until they lead to severe faults. These include voids, sharp‑edge discharges, surface discharge, loose insulation, corona formation and conductor‑to‑conductor activity. UHF PD monitoring identifies these issues early—even earlier than DGA or acoustic methods—helping asset owners prevent outages, reduce risk exposure and extend asset service life. As a solutions provider, we help customers deploy systems that overcome the limitations of conventional PD detection and ensure faults are detected with high sensitivity and strong noise immunity.

TECHNICAL

Features & Functionality

Functionality & Options

Scalable architecture: 1–6 UHF sensors per OCU; expandable up to 24 channels.
Real‑time PD trending: amplitude, discharge rate and correlation with load/OLTC operations.
PD localization: time‑difference‑of‑arrival techniques supported when multiple sensors are installed.
Remote monitoring and configuration: via secure Ethernet or fiber, with full software access.
Automatic self‑check: built‑in channel diagnostics and alarm logging.
Multiple communication protocols: IEC 61850, Modbus, SCADA relay outputs.
Long‑term storage: up to 5–10 years of PD history for trending and reporting.

Key Technical Specifications

UHF Sensor Inputs: 1–6 channels, expandable to 24.
UHF Frequency Range: 300–2100 MHz.
Sensitivity: −75 dBm to −80 dBm.
Dynamic Range: 70 dB.
Sampling Rate: 15,360 samples/s @ 60 Hz.
Noise Channel: Dedicated external noise‑antenna input.
Environmental Rating: IP66; operating range −25°C to +55°C; 5–95% humidity.
Communications: Ethernet (RJ45/fiber), IEC 61850, Modbus.
Data Storage: Solid‑state drive supporting multi‑year retention.

EXPERIENCE

Projects featuring Qualitrol Condition Monitoring

Explore project highlights to see where Qualitrol Condition Monitoring is making an impact.

For tailored advice on whether this solution suits your network, please connect with our team here.

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ADVANTAGES

Why Choose Qualitrol Partial Discharge Monitor

The Qualitrol QPDM is a next-generation, continuous online partial discharge (PD) monitoring system for transformers and small GIS. Utilizing Ultra High Frequency (UHF) technology, QPDM provides real-time detection and analysis of PD activity, enabling asset owners to identify insulation defects early, optimize maintenance, and prevent catastrophic failures.

Access to Industry‑Proven
UHF Technology

Qualitrol’s field-tested UHF PD systems have been trusted by utilities worldwide for more than two decades. These solutions provide superior sensitivity and interference immunity, making them ideal for early fault detection and continuous monitoring.

Flexible, Scalable Installations
for Any Transformer

Whether integrating sensors during transformer manufacture or retrofitting existing assets, we offer installation‑ready sensor options and fully scalable architectures. This allows customers to deploy monitoring at the level that matches their operational risk.

Dedicated Local Support
and Expertise

We assist with product selection, installation coordination, configuration, alarm setup and ongoing troubleshooting. Where needed, we also work with Qualitrol’s PD specialists to support advanced diagnostic analysis, ensuring customers get the most value from their monitoring systems.

IMPLEMENTATION

Services & Support

Insulect offers comprehensive services and support for the products we specialise in, enhancing value for local utilities, major energy users, equipment manufacturers, and service operators.

LOCAL TECHNICAL TEAM

Our local technical team provides exceptional support and expertise, ensuring quick response times and personalised service to tackle any challenges that may arise during project execution.

ENGINEERING EXPERTISE

Through Qualitrol, our team utilises advanced technology and industry knowledge to assist customers.

PROCUREMENT & LOGISTICS

We facilitate smooth procurement and logistics processes by sourcing from trusted, proven partners and coordinating timely deliveries, ensuring projects remain on schedule and within budget.

TESTING & COMMISSIONING

Professional testing and commissioning support ensures that every transformer monitoring system functions safely and reliably, adhering to all regulatory standards and client expectations.

TURNKEY PROJECT DELIVERY

We are able to oversee every phase from concept to completion, providing comprehensive solutions that simplify complex projects and ensure successful outcomes.